The pump has been playing a very important role in modern industry. Whether for transporting water or chemicals, without the pump, much would be impossible.
Apart from breakdown, a common problem with the operating pump is that the valve in the bottom of an intake suction pipe loses its non-return function. When the motor is off, the liquid remaining in the pump system will back flow to the original storage tank and leave the suction pipe having air inside causing the pump to race and be damaged when the pump is operated again. Consequently, a so-called "self-suction pump" has been developed to eliminate the aforesaid drawbacks.
A conventional self-suction pump is comprised of a storage tank, a separating tank, and a pump wherein vanes are installed to draw the liquid inside the storage tank and recycle the liquid so as to draw out the air in the suction pipe. However, such a pump has following drawbacks:
1. It cannot be installed on existing non self-suction type pumps. PA1 2. The vane requires high pressure operation and is inconvenient to be adopted. PA1 3. The loss in efficiency ratio due to the back-flow cycle ranges from 2% to 12%.
Therefore, a supplying self-suction unit is needed.